Among the different types of mucocutaneous manifestations/features of chikungunya fever, pigmentary changes, especially a centrofacial freckle-like pigmentation, have been described in literature. In some studies, it was the most common clinical pattern of pigmentation. Here, we report similar cases of pigmentary changes in two adult Indian patients, which occurred after a subsidence of acute febrile episode and prompted the patients to consult a dermatologist.

Our first case, a 40 year-old-male with a history of high-grade fever, headache, severe arthralgia, nausea, vomiting, and a maculopapular rash all over the body (1 month ago) presented to us with pigmentation on his nose. The patient was hospitalized for fever which lasted for 2 weeks. IgM antibody test for chikungunya virus by enzyme linked immunosorbent assay (ELISA) method was positive during the febrile episode. After subsidence of the fever, the pigmentation on the nose appeared which deepened gradually and persisted. There was no history of any preceding dermatoses of the affected area or any prior drug intake just before the appearance of the pigmentation. On examination, mild, scaly, pigmented patches were seen on the tip of the nose and right nasal ala [Figure 1], classical of localized centrofacial pigmentation of chikungunya fever. A skin biopsy was performed, and histopathological findings were increased basal pigmentation, pigmentary incontinence and melanophages [Figure 2]. Hyperpigmentation cleared off with a course of 4% hydroquinone cream for 4 weeks.

Figure 1: Pigmented patches on the tip of the nose and right nasal ala

The second patient, a 47 year-old-male, presented to us with nasal pigmentation, arthralgia, and weakness. He had high-grade fever, severe arthralgia, and maculopapular rash (2 months ago). Similar to our first case, IgM antichikungunya virus antibodies were detected in the blood, during the first week of fever. Three weeks after the resolution of acute symptoms, nasal pigmentation started to develop. It progressed to attain the present status. Cutaneous examination revealed non-scaly, grayish-black pigmented macules over both sides of the inferior surface of his nasal ala [Figure 3]. There was also no history of any preceding dermatoses, prior drug intake, any use of nasal abuse substances or nasal decongestant and intranasal steroid. He did not give consent to undergo skin biopsy. On the basis of the history and clinical features, a diagnosis of postchikungunya pigmentation was made. However, in this case hyperpigmentation persisted even after applying mild topical steroid and emollient for 4 weeks.

Figure 3: Pigmented patches on the inferior surface of both sides of nasal ala

Among various mucocuateneous manifestation of chikungunya fever, different patterns of hyperpigmentation (centrofacial freckle-like macules, diffuse pigmentation of face and extremities, flagellate pigmentation, mucosal pigmentation of tongue and palate and pigmentation of existing acne lesions), maculopapular eruptions, apthous-like ulcers, transient nasal erythema, ecchymosis, vesiculobullous lesions, vasculitic lesions, and exacerbation of existing dermatoses were the most common findings described in literature.[1],[2],[3],[4] Hyperpigmentation was the most common cutaneous finding in a report by Inamdar et al.[1] and another by Seetharam et al.,[5] whereas it was second most common finding followed by erythematous maculopapular rash in a study by Riyaz et al.[4]

The exact mechanism of pigmentation is not known. Inamdar et al.[1] proposed a virus-triggered increased intraepidermal dispersion/retention of melanin. Nose and centrofacial areas are primarily affected. Predominant affection of these sites and exacerbations of the pigmentation on exposure to sunlight indicate the possibility of the role of ultraviolet radiation exposure in the pattern of distribution of this pigmentary anomaly. Hyperpigmentation of skin may persist for months after the remission of the acute febrile episode. This may be treated with topical hypopigmenting agents such as hydroquinone with or without short-course topical steroids. Photoprotective measures including the usage of sunscreens should also be advised.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.